Radio control system for movable maps



Nov'. 4, 1941. E. w. HAWK 2,261,252

RADIO CONTROL SYSTEM FOR MOVABLE MAPS Filed Oct. 9, 1959 5 Sheets-Sheet 1 www Nov. 4, 1941. E. w. HAWK RADIO CONTROL SYSTEM FOR MOVABLE MPS Filed Oct'. 9,' 1939 5 Sheets-Sheet 2 Nov. 4, 1941; E. w. HAWK 2,261,252

RADIO CONTROL SYSTEM FOR MOVABLE MAPS Filed oct. 9, 1939 5 sheets-sheet s Ola-'.5 if sa 'www Nov. 4, 1941.

E. W. HAWK RADIO CONTROL SYSTEM FOR MOVABLE MAPS Filed Oct. 9, 1959 5 Sheets-Sheet 4 lll" Nov. 4, 1941. E. w. HAWK 2,261,252

RADIO CONTROL SYSTEM FOR MOVABLE MAPS F'iled Oct. 9, 1959 5 Sheets-Sheerl 5 kW77 A554 A traveling at a lhigh Vsp adQWspeed. Y.

l' y Patented Nov.4, 1941 UNITED Es nADIo CoNrIto-L SYSTEM FoRMovABLE Eugene-William Hawk, Los` Angeles, Calif., as-..

. signor of thirty-live per centto James L. Read, Los Angeles, Calif., as trustee for himselfan'd yfor Paul S.,Read,- Omaha, Nebr., and thirtyf two and ,one-halfpe'r' cent to Leslie C'.` Isom', v

Los Angeles,r- Calif.

' f Application otbbe; 9, 1939, serial'No'. ,298377 'f 117' olaimfswrgso-z) This .application presents aninvention in an vimprovement particularly adapted to the navigation of airplanes on Acommercial routes, partic- '..ularly over land 'or land and sea havingl distinct fixed markings ofithe'course invorder lthat the fdispatcherand the piloto-r navigator `may be able to determineby a'moving map strip the/location of the airplane'on its particular route. y

In the operation of commercial airplane lines thesehave distinct routes over theground'and in some cases partly over the seas and certain yislands in which the route. to befollowed isqquite 1 ,definitely mapped which maps-usually show the mainftopographical features, the locationy o f the commercial "and emergency landing fields, the

,navigational beacons, the direction of the radio guidance beacons, and also the. .location of. the

radio vstationbeacons and other aids to aid Athe airplanes on their substantiallyndeiinite .and predetermined route.

' rMy invention f takes c-:ognizancey of .these features and by use of a moving strip map on the mapped. r-

In 'conjunction With the moving vmap. on .the

airplane, another feature ofv my invention in- ,clud'es a radio transmitter preferably ofthe :shortv Wave type which sends out a'signal, thetimingof which is in synchronism with the movement `of ,450 theimap and thus with the travelof theairplane overits course.' f. ,v A characteristic of the particular signal isthat, this is of an intermittent character` but the time The length of the time periodsv of the transmissionimpulses while constant is to a certain extent A'furtherffeature. ofmy.:v invention includes a second and similar movable strip map at the'dis'- p atchers4 oice, the advance of such map .being controlled by the radio signals receivedff'rom the transmitter on.A the 'airplane,v Thus, at eacljiv` instance that the map is advancedl on. thefairplane the/second and corresponding"ma/pv at `the. dispatchers office is also advanced the advan both cases being of thesame amount. vvQ Iherefore,. the dispatcher may" bybbSerV-ing vhis fmap v kdetermine atany timethe approximate .location of the` airplane 'overthe predetermined` mapped course or route. Manifestly, rtherefore, when the airplane is traveling at high speed rthe map inthe dispatchers ofce is advanced more `rapidlyfthan when the airplane is-traveling at a low speedl relative to ground, that yis itsmappedcourse;

4 In orderthat a suitabletype ofY apY utilized my invention in additioncomp'risesa vphysical construction of a strip map in Which'the course tobe followed by the airplane ,is .shown as la straight longitudinal line entending'longitu- `dinally of ,themapand preferably along thece'n- `ter line nov matterwhetherthe airplane course as ,mappedshfows angular turns v`or not, v'Ihese anguiar turns andthe course are indicated on the `map, themap .showing either thecompass or the true 'meridian and latitude dire v.tions of the cours e. 1 v f o. A further characteristic. of the map3is thatthis illustrates the position and direction ofthe various radio navigationy beams, the location of the .vertical beams toidentify. location, and also the succession of airplane'beacons. Where practical. Ihis'strip map, in addition,v shows certain topographical features havingmain1y to ..do with mountafinsulanding vfields, and theY location of cities andtowns. g AA further characteristic of the lmap is l'that it sets forth a profile showjingfthe elevationtovvvhich; the airplane mustclimb to Y give adequate clearance over mountains,- etc.`

period during whichthe radio signal is trans- Q5 f mitted is constant, thus transmitting sufcient "radio energy for predetermined time periods.

d controlled as' tothe rapidity of the repeating, 5?'0 signals, dependent upon. the speed of the vehicle. In this construction, of course, argreater number of signals are vtransmitted when the.' airplane is" eed than when ,traveling at Another feature and instrument of ,my inven-v tion relates to thegr'ound speed operating and if ,'desired, Aground speed: indicating. device, which vv'may'have ashaft rotatablydriven by asuitable type of "airspeed indicator, Inf' conjunction with such s haft'my'invention includes aspeed 'control by which the pilot inayincreas'e orde'creas'ethe speed of a driven shaft or the like depending upon 1 the Wind `condition throughv which Hhe is' flying. Thus, if he isyin'g through still air,'the air .speed indicatorwill give the approximate ground ..speed,'however if he, is flying Witha tail Wind or into a; head vWind with the same engine fand ,propeller speeds, Ahe would obviouslybe flying 'may be with the tail wind at a higher ground speed and against the head wind with a smaller ground speed. The pilot therefore has under his control a friction or gear drive from the air speed indicator to give the approximate ground speed irrespective of the direction and velocity of the wind through which he may be ying.

My invention is illustrated in connection with the accompanying drawings, in which:

Fig. 1 is a front view of the moving map cabinet taken in the direction of the arrow I of Fig. 2, illustrating a transparent window through which the map is viewed together with 9, scale of linear and Vertical measurements together with a rotatable protractor.

Fig. 2 is a side View of the cabinet taken in the direction of the arrow 2 of Fig. 1 with the side door open exposing the internal feed mechanism for the moving map.

Fig. 3 is a face View of a section of a typical map constructed in accordance with my invention.

Fig. 4 is a side elevation taken in the direction of the arrow 4 of Fig. 5 of the constant time period circuit closer for the radio signal, parts being broken away.

Fig. 5 is a plan taken in the direction of the arrow 5 of Fig. 4.

Fig. 6 is a part elevation and part longitudinal section through the dash pot assembly taken on the section line 6 6 of Fig. 5 in the direction of the arrows showing the timing cam in one position of operation. f

Fig. '7 is a partial view similar to Fig. 6 showing the timing cam in another position.

Fig. 8 is an electrical diagram of the radio transmission circuit and of the electric operation of the pilots map.

Fig. 9 is an electrical diagram of the receiving station showing the radio receiver and the electrical operation of the map at the dispatchers oflice.

Fig. 10 is a side elevation partly broken away taken in the direction of the arrow I0 kof Fig. 11 of the timing control for the moving map and the radio transmitter.

Fig. 11 is a plan taken in the direction of the arrow Il of Fig. 10 partly broken away.

Fig. 12 is a vertical section on the line I2-I2 of Fig. 10 in the direction of the arrows.

Dealing first with the construction of Figs. 1, 2 and 3 of the map moving cabinet, such cabinet as a whole is designated'by the numeral II having a suitable base, side and back Walls, a top and with a transparent window I2 on the front. This window may be hinged if desired to open and close. For sake of clarity the map is not shown through the window. The window is ruled with a pair of parallel lines I3 extending from the bottom towards the top through which a scale of longitudinal distance on the map usually graduated in miles or suitable scale may be read. There are a series of transverse graduation lines III, these also running vertically and j indicating mileagedistance on the map considered transversely across such map. At one margin of the window there is a vertical graduation in parallel lines indicated at I5, this representing elevation as in feet above sea level or if desiredI A datum line I8 is drawn across the glass preferably intersecting at transverse graduations I4, the lelevation scale I5 and intersects the center of the protractor I6. This line represents the line on which the plane is located as the map moves concurrently with the movement ofthe aeroplane.

The equipment for moving the map may be any suitable desired arrangement for either continuouslyor step by step moving a strip map. The strip map moving assembly is designated by the numeral 25, Anote Fig. 2, in which the reel 26 is indicated as winding in the map and the reel 21, as unwinding such map. These reels are mounted on suitable axles and are shown located in the upper part of the cabinet. The strip may designated by the numeral 28 has a face portion 29 moving downwardly back of the window I2. The direction of travel is illustrated by the arrows. The map is guided over rollers 3B at the bottom and 3| at the top and a further portion over the idler 32. The strip map is positively driven by a feed between rubber covered feed rollers 33 and 34 which engage the periphery of a driven feed roller 35 preferably formed of metal. This metal roller 35 is driven in any suitable manner and thus simultaneously feeds the map from one of the reels towards the window and back towards the other reel. In a particular gear train illustrated, a gear 36 is connected to the metal roller 35. This meshes with an idler gear 31, the latter is driven by a driving gear 38, this latter being connected to a worm gear 39 driven by a worm 40, this latter being actuated by a shaft 4I driven by an electric motor 42 or the equivalent. The reels are actuated by providing a pulley 50 over which operates a slip type of belt 5I and this passing over complementary pulleys 52 on the reels. The pulley 5? is connected to and driven in conjunction with the gears 38 and 39 and the belt 5I is of a type provided for slippage such as the helically coiled wire belt. This operates the reels in a sufficient manner to take up on the map as it is fed to the reel and to discharge the map from the other reel, the slip compensating for the diierence of diameter of the rolled map on the reels. v

The strip map of Fig. 3 designated by the assembly numeral 15 has the following characterlistics: a scale 16 being a longitudinal measure in miles or the equivalent is ruled longitudinally of the strip intermediate the edges. TlL's leaves a face section 11 giving certain topographical features of the terrain over .which the aeroplane course is laid together with the various guiding beacons, etc. A center band 18V is dened between two lines preferably in the center of the map and where the aeroplane is to fly on a radio beacon, such beacon is illustrated as coincided with the band. For instance in the lower portion of the section of the map a compass bearing such as 317 degrees indicated at 19 and the directional arrow indicate a radio beam, the source of which is not shown on which the aeroplane is to fly as it is presumed that the plane is ying as to the map from the bottom towards the top, therefore the map is moved downwardly as above mentioned in the cabinet past the' window. The cross line 8l represents a section of the map where the plane deviates from the radio beam indicated at 19 and 8KB. This original beam is shown divergent'as at 82. The plane then follows another beam designated 83 having the compass bearing of 333 degreeswith the arrow pointing upwardly, the source of this latter beam yas 119 degrees.

cated at 95.

'reverse readings.

isnot indicated. The course on the beam 83 vis flown until another transverse line 84 is shown on the map when the aeroplane comes intov the field of a third radio beam 85 indicated by the compass bearing 320 degrees with the arrow.

This is at the. upper section of the broken map.

The map also has a heavy ruled'line 90 which defines a true meridian bearing, this being shown In View of the course changing at the lineA 8| and 84, this heavy meridian line also changes its angle. It indicates to the pilot his relation to this meridian course. It is to be understood that if the course is mainly east and west, this heavy line may indicate a parallel of latitude. The map indicates prominent features having to do with the navigation of the areoplane in which a main radio control station is indi- This may be the station sending out the beam indicated 19,80 and 82. At the line of change of course 8|, there is indicated a radio control station 96, this being indicated -as having a vertical or cone beam to show where -the change of course takes place.

provided with the letters A, 91, and N, 98, which are call letters from the station transmitting the navigation beam and indicate to the pilot whether he is on or off the beam. Various other features of topography are shown such as towns or landing fields 99, a lake and other details .may be shown. The map has reverse readings on the beams indicated at I 0| showing 137 degrees with` a downwardly pointing arrow, this giving the reverse reading of a beam when iiying inthe opposite direction relative to the map, that is, from the top towards the bottom in which case the map would be presumed as moving upwardly as to the front of the cabinet.

All ofthe radio beams are marked with their Prominent features of the topography which may be of a guide are shown, a railroad track being indicated at |02. Manifestly in a inished map many other features are exhibited but for sake of clarity the elevation 'contours are preferably omitted. These conn tours are shown at the side of the map indicated at and may be graduated in a suitable vertical scale preferably from a sea level and in this case an extensive plainA is indicated at |06 and -a mountain range at |01. These become exhibited on the map long prior to the particular serving the ground over which he is flying and noted points su'ch as radio or light beacons, the pilot can determine how many miles he is flying to one side or the other of his center or true proper course.

The radio timer of Figs. 4 to '7 and designated by the assembly numeral |25 is for the purpose of giving a radio signal of constant duration no matter how rapidly the signal is repeated, that is, when the areroplane is travelling slowly over the ground the signal is repeated slowly and when travelling fast, repeated much more frequently but the time period of the duration of the actual signal is constant, this being for the vpurpose of transmitting sufficient energy to operate through the medium ofy relays the moving map at the dispatchers office. In the construction a suitable frame |26 is shown as havinga standard The map is |21 with an arm |28 on which arm there is mounted a metal tube |29 having a metal guide block |30 at the top. An insulating bushing I 3| is secured to the metal tube and to the guide |30 and itself supports a complementary metal f tube |32. In this tube there is an upper slidable Contact pin |33, this being depressed by a spring |34 bearing against a closure plug |35 threaded to the upper end of the sleeve |32. The lower contact pin |36 is also normally depressed by a spring |31, the lower end |38 of the pin |31 extends below the arm |28 and is in a position to be engaged by the surface bearing end |45 of a sliding arm |46.

This arm is mounted on a support |41, the arm having a slot |48 through which extends a' pin |49. A spring |50 normally retracts the arm. Such arm has a lugV |5| on its underside, this being provided with an inclined tooth |52. The arm is guided in its movement by a bracket |55 so that it has a straight line motion except for'a slight up and down oscillation relative to the pin I 49. The purpose of the moving arm is to develop a time control indicated by the assembly |60 which has a dash pot I6I with a graduated air orifice |02, the piston |63 has its piston rod |64 pivoted to a stud |65 extending upwardly from the main portion of the rod I 46. Therefore on account of the tension of the spring. |50 urging the retraction of therod and the piston into the dash pot, the rate of return is controlled by the orifice |62 for the outlet of air. The air is expelled through lan orice |66 when the rod is being thrust upwardly. The movement of the rod is controlled by a speed responsive cam |10,

this being illustrated as mounted on a shaft I1AI. This is illustrated as a square type of cam having the flat sides |12, the operating tooth |13 and the rise or lift surface |14. The cam rotates dicated in Fig. 6 in which it will be seen that the upper surface |45 is advanced a considerable distance under the lower end |38 of the contact pin |36. As soon as the teeth on the cam and on the lug release, the bar is raised on the lift section |14 of the cam which brings the surface |45 into engagement with the lower end |38 of 'the lower pin lifting this upwardly to make a contact with the lowerend of the upper or shifting pin |33. The spring |50 is now free to retract the arm I 46 but the arm is maintained in its raised positiontherefore maintaining the electrical contact between the pins |36 and |33. This time period is regulated by the timing assembly |60 of the dash pot so that this time is always of the same length no matter whether the cam |10 is rotating slowly or at a high speed and its rate of rotation is controlled by the speed of flight of the areoplane. The electric circuit features of the contact pins |33 and |36 are given in the electrical diagram.

The speed responsive cam |10 (note particularly Figs. 4, 5, 6 and '7) is operated by the mechanism hereunder described. My invention however is not limited to the specic details shown. It will be notedrthe shaft I1I is journalled in suitable bearings and has a driven extension IBI with a wormgear |82. This is rotated by a worm |83 on a suitably journalled worm shaft |84. This shaft has a coupling |85 to which is connected a rotary shaft or rotating cable |86, this latter being driven by mechanism operated in conjunction with the speed of the aeroplane through the air but compensated to operate at an approximately correct relation to the ground speed of the aeroplane, that is, the speed of travel over the actual ground and in relation to the moving map.

As above mentioned, suitable types of radio transmission which give a constant time of actual transmission may be utilized with my equipment together with suitable compensating means to give approximately the ground speed of the aeroplane irrespective of the direction of the wind. In Fig. 8 I illustrate in diagram a radio transmitter 206 in which one of the stages is indicated at 26| by a conventional radio tube. This has a cathode 262 connected by a lead 253 to the upper contact pin |33 shown in detail in Fig. 4. The lower and cam operated pin |36 is connected by a lead 204 to a ground of the radio set. The Various stages of amplification and of the power tube are not shown in the radio transmitter but the output, that is, the signal emanates from the antenna 205. This gives a broadcast of the desired short wave signal always of a constant duration as to its time.

The moving map in the aeroplane preferably in the navigators or pilots cabin is operated by a circuit indicated at 2|0. This illustrates a motor 2||, a source of power 2|2, the connections through a main opening and closing switch 2|3,

r a reversing switch 2M to reverse the direction of the motor. The contact pins |33 and |36 (Figs. 4 and 8) as above described, close the radio transmitting circuit periodically and for uniform time periods of closure. These pins are also utilized to close the motor circuit to move the map during the time the radio transmitter is closed. The motor circuit, presuming the main switch 2|3 is closed, employs the electric leads 2|5 and 2|6, 2|5 including part of the radio connection lead 203 and through the contact pins |33 and |36 when these are in closed position. In order to block interference of the motor and radio transmitter circuits a condenser 2|'| is bridged across the leads 2|5 and 2i6 and in both of these leads there are radio frequency choke coils 2|8. By this circuit it will thus be seen that during the time period that the signal is being broadcast by the closed contact between the pins |33 and |36, the motor 2| l is also energized and moves the map in the aeroplane, this being constructed and operated as described above in connection with the map moving equipment.

The receiving circuit and operating mechanism at the dispatchers oflice is indicated in Fig. 9 and designated by the numeral 230. This has-the receiving antenna 23|, a radio receiving set 232 not illustrated in detail. This has proper amplication and the output operates a relay 233, this relay having one side grounded as indicated at 234. The motor 240 is illustrated as operated by a source of power 24| shown as a battery, the connections through the relay through a main opening and closing switch 242 and a reversing switch 243. This latter allows changing the direction of the motor and hence the direction of movement of the strip map. It will thus be seen that during the time periods that the radio signal is being received the relay is closed and therefore the motor is energized thus moving the map for a predetermined short time period at the dispatchers office. From a description of the mechanism in the aeroplane its map is also simultaneously moved, therefore both maps are moved at the same time and the same distance, thus the pilot can ascertain his position of ying relative to his own map and the dispatcher by interpreting his map may also note the aeroplane as being at the same position.

As above mentioned, the operating cam |10 of Figs. 4, 6 and '7 is utilized to close the circuit 0f the radio transmitter by making the contact of the movable points |33 and |36 and in addition these points cause the make and break of the circuit energized electric motor for moving the map on the aeroplane. This cam or the equivalent may be actuated in any suitable manner to be driven at a speed proportionate to the travel of the aeroplane over the ground. In Figs. 10, 11 and 12, I illustrate a suitable friction gear drive by which the pilot or navigator may compensate for flying with or against the wind or diagonal winds compared with the speed through still air. In this construction the gear assembly is indicated by the numeral 256. In this instance a shaft 25| is connected to and driven by a suitably actuated air motor or some device which gives a speed through the air. If desired it may be connected to the engines where it is known that at designated color speeds the aeroplane will travel through still air at a known rate. I do not illustrate theparticular drive connection for the shaft 25| as this forms no immediate part of my invention and I may use equipment now known. In the illustration the shaft 25| may be considered as a driving shaft so far as the gear train is concerned and has a worm 252 thereon driving a worm gear 253 mounted on a vertical shaft 254. This shaft has a friction disk 255 on its upper end, the vertical shaft 254 and the shaft 25| having suitable journals. A splined driven shaft 266 is mounted in suitable journals and has a friction wheel 26| slidably mounted on the shaft provided with a key fitting in the splines. A suitable frame such as 262 is illustrated for mounting the shaft 260. In order to shift the friction wheel 26| longitudinally of the shaft, I provide a screw threaded yoke 263 which has fingers 264 engaging on opposite sides of a collar 265 to secure to the friction wheel 26|. This may have one finger engaging a reduced neck if desired. A speed regulating screw feed shaft 210 is also journalled in the frame and has its threaded portion meshing with the threaded yoke 260 and 263. 'Ihis shaft 210 has a manually operated register dial 21| which is calibrated as to the component velocity of winds, the components being resolved to direct head and tail winds or if desired the scale in graduations may take into consideration diagonal or quartering winds.

The pilot or navigator by knowing the velocity of for instance a head wind, a tail wind or the component of diagonal winds resolving as to a fore and aft direction, may set the dial and hence the shaft 21|), thus shifting the yoke 263 and the friction wheel 25| to compensate for head or tail winds. It is presumed that in the position illustrated the friction wheel 26| is set to rotate the shaft 26B at the desired speed when the aeroplane is travelling through still air and hence the air speed is equal to the speed over the ground of the aeroplane, then if the aeroplane is travelling with a tail wind, as the speed over the ground increases, the dial 27| must be set to give the proper increase in speed of the shaft 2,66. Likewise if the plane is travelling into a retarding nals to the f dispatcher.

'though my invention has been described as rehead' wind.' the.y dial"2'l|` is `likewise vset and the speed of the shaft 260 retarded.l For 'sake of simplicity of illustration, the shaft 26.0; is shown as; driving the flexiblel orequivalent. shaft |86 which operates the .camA vI'Ill Vthrough the gear l trainof Iigs. 4 through 7. It'Will hence be seen that `the pilot or navigator may'have an accurate control of the' 'ratecf operation ofthe timing cam and hence of the moving map and thefrequency of repetitioniof the radio signals transmitted; t

a Q;Therefore should" the pilot orV navigatorv` by navigationalzor ground observation fin'dthat the map in the cabinet ofthe aeroplane does not ac-v errors discovered by the pilot or navigator. It is of course obvious that the shaft 25| may be driven v in anyv suitable manner Aand in some cases it'may be Adesirable to have-this manually operated byr a ypilot or navigator to shift'the map in accordancefwith .the observationsv of the navigator. My

inventionconsidered broadly comprehends having. a map and a positionindicating device on an aeroplanel to designate the location o f the aeroplane in reference to the map. A relative movement is'established between the map and the position'indicating .means by a suitable device or mechanism.A Interconnected. with the aeroplane locating means as to the map and the position indicator,` my invention includes the radio transmitter'which operates at desired intervals'of time and preferably forr designated time periods; This radio signal. is thus'a control signal to the dispatchers depot. r It is obvious that if desired the map and the positions indicatori. may be relatively moved byv somevman'ual device and the radio transmitterfoperated vins'ome type of a synchro-v nous. mannerto send out the desired control sig- It is obvious that allating principally to aeroplane travel and navigation, it isvapparent that a' similar or equivalent construction may be vused inconnection with a sequence 'of radiol signals correlated Withthe means toirel'atively move the map and thefposition indicating means, a second map" constructed and adapted for mounting ata. ground depot, a

second means to'indicateth'e position ofjthe vehicle on the second map and means controlled by thereceived radio signal` at such'depotto relativelymove the second mapand the second plosition indicating means to indicate at the depot the same change of position of the'rst map andthe iirst indicating means on thevehicle. Y

2. In a'devicefof the typedescribed, a vehicle havingV a-rs't map suitably mounted; afrst means to indicate the position of the vehicle'in reference to the map,v means to relatively move the .map and the position indicating means'pro-j yportioned to the advance Yof the vehicleandv thus indicatel the changing positions of the vehicle as to the map, means on the vehicle to'transmitu hicle on the second map andmeans controlled by the received radio signal at such depot to relatively move the second map andthe second po- `sition indicating means to indicate at the depotA the same change of position of the rst map and.

' the first indicating means on thek vehicle, the'rst and second maps each being movable in reference to its position indicating means, means on also be used 'in` connectionl With-land transports such as longV distance stage or bus'service. yIn

4 thisv latter case frequently the dispatchers do not y lizd in connection with bus servicesin cities and towns, Istreet'ca'r service and the operationof railway trains.

-fVarious changes maybe made in the details of the'. construction Without departing from' thel spirit-or scope of thev invention as defned bythe .appended claims. i

',Iclaim f '51.1 Infa device :of-the type described; Ya'v'ehicle f l'ia'vinga rst-map suitably mounted;a first means to indicate the position of the vehicle in reference to the map, means to relatively move the map and the position indicating means proportioned to the 'advance of the 'vehicle :and thus indicate theffchanging positionsfof*- thel vehicle" asjtothe' map, means on'the vehicle to transmit the vehicle to transmit the radio signalsin synchronism With deinite movements of the first map, the radio signal control means at the depot being associated with means-for moving the second map at the depot in synchronism with 'the movement of the rst map on the vehicle;

3. Ina device of' a type described, atvehicle having a first movable strip map, means to move such rst map distancesy proportioned tothe speed of the vehicle, a first means vto indicate the position of the vehicle in reference to"l the first map, means to vtransmit a sequence of radio signals from the vehicle proportionedr to the speed of the vehicle and the movement of they' iirst map, a second and similar movable strip y map constructed and adapted for location at a ground'depot, 'a radio receiver at such depot,A

means controlled by the received signal from the transmitting means on the vehicle to move the second map in synchronism with the movement of the rst map and a second means at the depot to indicate the position of the vehicle in reference to thev said second map,

4. In avdevice'of a type described, a vehicle', I

having a first movable strip map, means to move such rst map -distances proportioned to the speed'of the vehicle, arst means to indicatethe position of the vehicle in reference lto the firstl map, means to transmit a sequence of radio signals from the vehicle proportioned tothe speed of the Vehicle and the movement of the iirst.A

map, aj second and similar movablestrip map ting means on the vehicle. to movethe second map rin synchronism with the movement of ther first map and a second means at the depot to indicate theA position o f thevehicle in'reference, to kthe said second map, the radio transmitter' havinggmeans to transmit a signal always of, constanttime vduration but of av varying' time lapse'period thetime lapseperiod being' propor'l tioned to the speed of the vehicle and the ad. vance movement of the first strip map,V

5. `In a device as described, a vehicle4 having a first movable strip map with a first position indicating means associated with such map, means to'move the map proportionate distances to the travel of the vehicle, means to transmit radio signalswith a frequency of timing proportioned to the speed of the vehicle and to the advancement of the map.

6. In a device as described, a vehicle having a first movable strip map with a first position indicating means associated with such map, means to move the map proportionate distances to the travel of the vehicle, means to transmit radio signals with a frequency of timing proportioned to the speed of the vehicle and to the advancement of the map, a radio receiver at a ground depot, a second and similar movable strip map with a locating means associated therewith at the 'depot and means controlled by the radio signal received at the depot to move the second map amounts similar to the movement of they first map.

7. In a device as described, a vehicle having a map and a position indicating means for location of the vehicle as to the map, means to relatively move the map and the position indicating means, means to transmit a radio signal controlled by the relatively moving means .for the map andthe indicator, a second map at a depot with a vehicle position indicating means, a radio receiver at the depot and means controlled by the signal received to relatively move the second map and its indicating means to show the same position of the vehicle on the second map as on the first map.

8. In a device as described, a vehicle having a map and a pcsticnindicating means for location of the vehicle as to the map, means to relatively move the map and the position indicating means, means to transmit a radio signal controlled by the relatively moving means for the map and the indicator, a second map ati@ depot with a vehicle position indicating means, a radio receiverrat the depot and means controlled by` the signal received to relatively move the second map and itsV indicating means to showthe same position of. the vehicle on the second map asgon the rst map, the radio transmitter' having a circuit closing means with a constant time con-4 trol to maintain such circuit closed for the, same period at each closure and means to operate the circuit closer at variable frequencies depending upon the relative speed changes of the rst map and the rst position indicating means.k

9. In a device as described, a Vehicle having a movable strip map with a vehicle positionindicating means associated with the map, means.

to move the map in a step by step manner, a radio transmitter, means to transmit signals therefrom timed with the step by step-movement ofthe map.

10. In a deviceas described, a vehicle having a movable strip map with a vehicle position indicating means associated with the map, meansI to move the map in a step by step manner, av

receivedradio signalto move the secondmlapinq a step by step `manner in synchronism with the movement of the first map.

11. In a device as described, the combination of a cabinet having a window, a strip map, means to move the map with the face side thereof in the cabinet and exposed through the window, the cabinet window having graduations thereon indicating distances proportionate to that of the map, the map having a` center band indicating the line of travel of a vehicle and the window having a rotatable protractor, the center of which aligns with the center of the center band of a map.

121. In a device as described, the combination of a cabinet having a window with means to indicate a position of a vehicle, a map having a center band showing the route of travel of a vehicle and means to move the map whereby the position indicator aligns with places over the `map conforming toV the location of the vehicle in` relation to the ground over which it is travelling.

13. In a device as described, the combination of a cabinet having a Window with means to indicate a position of a vehicle, a map having a center band showing the route of travel of a vehicle and means to move the map whereby the position indicator aligns with places over the map conforming to the location of the vehicle in relation to the ground over which it is travelling, the map having linealV distances marked thereon and visible through the window together with` elevational contours presented in section and visible through the window, the window having a transverse scale of distances to intersect the longitudinal distance measurements of the map and a protractor rotatable on the center defined by the vehicle position indicator on the window and the center line ofthe band indicatingY the travel of the vehicle.

14. Ina device as described, the combination of a cabinet with a window andl reels with astrip map wound thereon,` a feed means for the map, means to guide a section of the map located be-` tween the reels inside the window in a position for observation, means to, intermittently shift the map, the map having a` band thereon with` designations of radio navigation beams and radio beacons, the center line of the band having the compass direction of a sequence of radio beams whereby in the movement of the map the se-` quence of radio beams to be followed by an aero,-` plane valigns with the center line of the Window.

15. In the art described in which a vehicle and a depotr each are provided with a movable map of theV ground over which the vehicle is to travel. and each withan indicating means of the posi- ,tion of the vehicle relative to the map, the ve-v hicle having a radio transmitter and the depot-a radio receiver, the method consisting of in the,

vehicle moving the map at a rate proportionateA to the speed of the vehicle over the ground and indicating. on the depot map the position of the;

vehicle thereby locatingV the place on the ground' over which the vehicle is operating.

` 16. In al device as described an aeroplane, a map on the aeroplane ofy the ground over which theA aeroplane travels,means to move the, map

yat a rate proportionate to the speed of the aeromapdistances proportionate to the movement of the rst map,v a position Vindicating means associated with the second map to designate the position of the aeroplane on the second map in accordance With the position indicated on the first map and hence the position of the aeroplane to the ground over which it travels.

17. In a device as described, the combination in a vehicle of a movable strip map With a vehicle position indicating means associated lwith the map, an electro-mechanical means to move the map, a radio transmitter, a circuit closer having a connection to the electro-mechanical map moving means and to the radio transmitter with means synchronizing the map moving means and circuit closer for energizing the radio transmitter in conjunction with the moving of the map for the transmission of a radio signal.

EUGENE WILLIAM HAWK. 

